An exclusive report putting perspective on the week's most important developments.

SEOUL, Jan. 7 (UPI) -- As South Korea and the United States discussed ways to deploy U.S. military assets in response to recent North Korea provocations, Japan's nuclear regulator said no radioactive materials were collected in samples from Air Self-Defense Force jets.

U.S. and South Korea military pressure on North Korea is expected to escalate at the border after Pyongyang's announcement that it had tested a hydrogen bomb, South Korean newspaper Hankook Ilbo reported Thursday.

South Korean Defense Minister Han Min-koo said Thursday that U.S. Defense Secretary Ashton Carter had reaffirmed U.S. commitment to the defense of the peninsula, including all the extended deterrence capabilities of the United States. South Korea press reported the Pentagon could possibly demonstrate a show of force by deploying the B-52 long-range bombers and B-2 stealth strategic bombers.

In the past, North Korea had expressed opposition to the deployment of U.S. aircraft near the peninsula. The B-52 is capable of striking North Korea commander hideouts with nuclear missiles. The B-2 is capable of secretly infiltrating North Korea territory undetected, while equipped with nuclear weapons.

The B-52 and B-2 bombers are the weapons "Kim Jong Un fears the most," an unidentified South Korea military official said.

North Korea's claims of a hydrogen bomb test, however, have yet to be verified.

Japan press reported confirmation would take time, and samples collected by Tokyo's Air Self-Defense Force jets on Wednesday showed no traces of radioactive materials.

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